<template>
  <div>
    <label for="all">全选:</label>
    <input type="checkbox" id="all" v-model="all" />
    <ul>
      <li v-for="(item, index) in arr" :key="index">
        <input type="checkbox" v-model="item.c" />
        <span>{{ item.name }}</span>
      </li>
    </ul>
  </div>
</template>

<script>
export default {
  data() {
    return {
      arr: [
        { name: "猪八戒", c: true },
        { name: "孙悟空", c: false },
        { name: "唐僧", c: false },
        { name: "白龙马", c: false },
      ],
    };
  },
  computed: {
    all: {
      get() {
        return this.arr.every((item) => item.c);
      },
      set(value) {
        console.log(value);
        this.arr.forEach((item) => (item.c = value));
      },
    },
  },
};
</script>
